Step for a modular staircase and relative building method

ABSTRACT

A step for building a staircase, which includes: a base frame provided with a flat support surface configured to be laid and fixed on a ground, a footboard provided with a flat walkable surface, which is hinged to the base frame according to a hinging axis parallel to the walkable surface and to the support surface of the base frame, and a locking arrangement to lock the footboard with respect to the base frame in a plurality of different angular positions around the hinging axis.

TECHNICAL FIELD

The present invention relates to pre-built steps for building staircases on sloping grounds, as well as a staircase built with said steps and a method for building said staircase.

PRIOR ART

Building a staircase on a sloping ground, such as a rolling hill, a slope or any other declivity, generally involves digging the ground and building a set of mutually overlaid steps in this digging.

The steps may be built with any material fit for the purpose, for instance wood, stone, masonry or cement.

However, digging and building the steps on the spot, makes building these staircases a relatively complex, time-consuming and expensive activity.

In many circumstances, such as when the staircase has mainly a functional purpose and/or is not required to have a significant aesthetic quality, the complexity, timing and costs related to building thereof may be undue.

DISCLOSURE OF THE INVENTION

In the light of the above, an object of the present invention is to allow building steps on sloping grounds in a simple, quick and rather cost-effective way.

Another object of the invention is to make a staircase without having to significantly alter the structure of the ground on which it will be built.

A further object is to build a staircase that may be dismantled and re-assembled in another place.

These and other objects are reached thanks to the characteristics of the invention as set forth in the independent claims. The dependent claims outline preferred and/or particularly advantageous aspects of the invention but not strictly necessary for its attainment.

In particular, an embodiment of the present invention makes available a step for building a staircase, which comprises:

-   -   a base frame provided with a flat support surface adapted to be         laid and fixed on a ground,     -   a footboard provided with a flat walkable surface, which is         hinged to the base frame according to a hinging axis, parallel         to the walkable surface and to the support surface of the base         frame, and     -   locking means adapted to lock the footboard with respect to the         base frame in a plurality of different angular positions around         said hinging axis.

Thanks to this solution, the step can be efficiently used as a modular element for building staircases quickly, easily and cost-effectively.

In fact, the support surface of the base frame may be efficiently laid and fixed on any sloping ground, without having to obtain a preliminary digging, but only taking care of arranging the hinging axis in a horizontal way.

At this point, duly adjusting the mutual angular position between the base frame and the footboard with respect to said hinging axis, it is advantageously possible to change the orientation of the walkable surface depending on the ground grade, making sure that it is always substantially horizontal.

After locking the footboard in this angular position, a first step of a staircase is thus obtained allowing people to easily and safely go up and down the sloping ground.

This staircase may be possibly enlarged by arranging on the sloping ground a second step that is similar (e.g. equal) to the first step and in the same ways as previously set forth.

This second step may be positioned above or below the first step, in such a way that the hinging axes of these two steps are parallel to but spaced apart from each other, and preferably though not necessarily, such that the walkable surfaces of the two steps are aligned along the direction of maximum grade of the sloping ground.

In the same way a third similar (e.g. equal) step may then be added to the previous ones and so on until a staircase of the desired length is obtained.

It is thus clear from what set forth above that, thanks to the use of one or more steps as per the present invention, it is advantageously possible to build modular staircases on sloping grounds quickly, and without having to carry out significant and expensive ground digging operations.

These steps are also advantageous as they can be dismantled and re-assembled several times, for instance to move the staircase on other grounds or to build other staircases.

According to an aspect of the present invention, means for locking the step may comprise at least a connecting element adapted to rigidly connect a primary coupling portion of the base frame to a secondary coupling portion of the footboard, said primary coupling portion and said secondary coupling portion being both spaced apart from the hinging axis.

This aspect of the invention provides a very simple and efficient solution to lock the step footboard in a preset position that is angular with respect to the base frame.

Another aspect of the invention provides that the base frame may comprise a plurality of distinct primary coupling portions spaced apart from the hinging axis and that the connecting element is adapted to rigidly connect the secondary coupling portion with any one of said primary coupling portions.

Thereby, the connecting element itself may be efficiently used to lock the step footboard in a plurality of different angular positions with respect to the base frame.

In particular, the connecting element may be fixed to the secondary coupling portion by means of an articulated joint, such as by a bolt, defining an articulation axis that is parallel and spaced apart from the hinging axis.

Thanks to this solution it is possible to modify the footboard slope with respect to the base frame without completely dismantling the connecting element but simply rotating it with respect to the secondary coupling portion, until it reaches slopes that make it possible to be connected to different primary coupling portions.

In addition or in alternative to what above set forth, the footboard may comprise a plurality of secondary coupling portions that are spaced apart from the hinging axis and the connecting element may be adapted to rigidly connect the primary coupling portion with any one of said secondary coupling portions.

This solution also allows to lock the footboard of the step in a plurality of angular positions that are different from the base frame using the same connecting element.

In this case also, the connecting element may be fixed to the primary coupling portion by means of an articulated joint, for instance by means of a bolt, defining an articulation axis that is parallel and spaced apart from the hinging axis.

It is thereby possible to modify the footboard slope with respect to the base frame without completely removing the connecting element but simply rotating it with respect to the primary coupling portion, until it reaches slopes that make it possible to be connected to different secondary coupling portions.

In order to increase the number of obtainable angular positions, it is in any case preferred that the base frame may comprise a plurality of distinct primary coupling portions spaced apart from the hinging axis, that the footboard may comprise a plurality of distinct secondary coupling portions spaced apart from the hinging axis, and that the connecting element is adapted to rigidly connect any one of said primary coupling portions to any one of said secondary coupling portions.

According to an aspect of the invention, locking means may comprise at least two of the aforesaid connecting elements, which may be mutually spaced apart in a direction parallel to the hinging axis.

Thanks to this solution it is advantageously possible to increase the stiffness of the connection between the base frame and the footboard, making the step more stable and safer.

Another aspect of the invention provides that each connecting element may be conformed as a rod (or tip) having and end connectable to the primary coupling portion and the opposite end simultaneously connectable to the secondary coupling portion.

This aspect of the invention provides a particularly simple and efficient solution for building the connecting element.

According to another aspect of the invention the base frame may comprise one or more first through holes, each of which is adapted to receive an anchoring peg adapted to be driven into the ground by passing through said first through hole.

Thereby, the base frame may be stably fixed to the ground easily and quickly.

Another aspect of the invention provides that the base frame may comprise one or more second through holes, each of which is adapted to be overlaid on a corresponding first through hole of another similar (e.g. equal) step to receive the same anchoring peg.

Thanks to this solution, each anchoring peg allows not only to stably fix to the ground two steps at the same time but also to connect these two steps between each other, keeping them at a preset distance, thus contributing to build a more stable and safer staircase.

According to another aspect of the invention, the step footboard may comprise a slab-shaped element making available the walkable surface and a perimeter framing which supports and surrounds said slab-shaped element.

Thanks to this solution it is advantageously possible to simply and cost-effectively build different models of step, for instance producing each time the slab-shaped element with different finishes and/or materials, among which metal, wood, plastic, cement or stone.

Another embodiment of the present invention makes available a modular staircase which comprises a plurality of steps each having the above underlined characteristics, which are mutually connected and arranged with the respective hinging axes parallel and spaced apart from each other.

A further embodiment of the present invention finally makes available a method for building a staircase, comprising the steps of:

-   -   prearranging a plurality of steps each having the above         underlined characteristics,     -   placing these steps at different heights on a sloping ground,         making sure that the support surfaces of these steps lay on the         ground and that the hinging axes are horizontal, parallel and         spaced apart from each other,     -   fixing the base frame of each step to the ground,     -   positioning the footboard of each step with respect to the         corresponding base frame, by making it rotate around the         respective hinging axis, in such a way as to arrange the         respective walkable surface substantially horizontal,     -   locking the footboard of each step to the corresponding base         frame, in such a way as to prevent the mutual rotation around         the respective hinging axis.

This embodiment takes advantage of the innovative characteristics of the above described steps and allows to build a staircase in an extremely simple and quick way.

Obviously it is not required that all the stages are carried out exactly in the above suggested order. For instance, if the ground grade is known, the slope of the footboard may be adjusted and locked before fixing the base frame to the ground itself.

An aspect of this last embodiment of the invention provides that the base frame of each step may comprise one or more second through holes, and that fixing the step base frame to the ground may comprise the stages of:

-   -   overlaying each second through hole of the base frame of a step         to a corresponding first through hole of another step, and     -   driving an anchoring peg into the ground by passing it through         both said first and second through holes.

As previously mentioned, this aspect of the invention not only allows to fix the step to the ground but also to connect them with each other and keep them at the proper mutual distance, making it possible to obtain a more stable and safer staircase.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and advantages of the invention will be more apparent after reading the following description provided by way of non-limiting example, with the aid of the figures illustrated in the accompanying drawings.

FIG. 1 is an axonometric view of a step according to an embodiment of the present invention.

FIG. 2 is a side view of the step of FIG. 1 .

FIG. 3 is an axonometric view of a staircase made with a plurality of steps as the one shown in FIG. 1 .

FIG. 4 is a side view of the staircase of FIG. 3 .

FIG. 5 is an axonometric view of a second staircase made of a plurality of steps as the one shown in FIG. 1 .

FIG. 6 is a side view of the staircase of FIG. 5 .

DETAILED DESCRIPTION

From the mentioned figures a pre-built step 100 can be seen that is adapted to be used as a modular element for building staircases 500 on sloping grounds T, such as a rolling hill, a slope or any other declivity.

The step 100 comprises a base frame 105, which can be made for instance of steel or other metal material.

The base frame 105 has a support surface 110, which is substantially flat and adapted to be laid coplanar on the ground, preferably directly contacting the latter.

In the example shown, the base frame 105 comprises a slab-shaped body 115 which has a lower surface defining the support surface 110 and an opposite upper surface.

This slab-shaped body 115 may have a substantially rectangular perimeter with a front edge 125, an opposite and parallel rear edge 130, and two side edges 135 (only one of which is visible in the figures) that are mutually opposite, parallel and both orthogonal to the front edge 125 and rear edge 130.

Even though the slab-shaped body 115 shown in the figures is completely closed and continuous, it is not excluded that, in other embodiments, it may have one or more openings lightening the structure and thus take the shape of a framing or flat grid.

On the upper surface of the slab-shaped body 115, two spars 140 may be fixed, for instance welded, which are oriented parallel to one another and mutually spaced apart.

For example, the spars 140 may extend with an axis parallel to the side edges 135 of the slab-shaped body 115 and may be each fixed at a respective one of said side edges 135.

In an axial direction, each spar 140 may comprise one front end 145 which projects out of the front edge 125 of the slab-shaped body 115 and a rear opposite end 150 which projects out of the rear edge 130.

In more detail, each spar 140 may comprise one first profile 155 with a C-transversal section defining a channel having the concavity directed to the opposite part with respect to the slab-shaped body 115 and which makes available two parallel and mutually spaced apart side walls, which rise perpendicularly with respect to the slab-shaped body 115 and extend parallel to the longitudinal axis of the spar 140.

This first profile 155 may have a first axial end from which a flat attachment 160 projects out, parallel to the slab-shaped body 115, which projects out of the front edge 125 of the slab-shaped body and defines the front end 145 of the respective spar 140.

The flat attachment 160 may be made in a single piece with the first profile 155, which also comprises a second and opposite axial end 165 which remains positioned above the slab-shaped body 115.

At this second axial end 165, each spar 140 may further comprise a second profile 170, which extends with an axis parallel (possibly coincident) to the axis of the first profile 155, which it can be fixed thereto (for instance welded) such to constitute an axial extension thereof.

For instance, the second profile 170 may be partially inserted into the cavity defined by the first profile 155, at the second axial end 165, and may axially project therefrom, extending above the slab-shaped body 115 towards the rear edge 130.

The second profile 170 may have a substantially rectangular transversal section.

Each spar 140 may further comprise a flat attachment 180, parallel to the slab-shaped body 115, which extends axially from the free terminal end of the second profile 170, such to project out of the rear edge 130 of the slab-shaped body 115 and define in practice the rear end 150 of the spar 140.

Regardless of what above described it must be specified that, in other embodiments, the spars 140 may be made in a completely different way.

In any case, at the front end 145, each spar 140 may have a first through hole 195, for instance having an orthogonal axis with respect to the support surface 110, which is adapted to receive an anchoring peg 185 to fix the base frame 105 to the ground on which it is laid.

The first through hole 195 may be for example obtained in the flat attachment 160 of each spar 140.

At the rear end 150, each spar 140 may further comprise a second through hole 190, having for example the axis orthogonal with respect to the support surface 110, whose function will be made clear later on in the present description.

The second through hole 190 may be for example obtained in the flat attachment 180 of each spar 140.

Even though in the example shown first through holes 195 and second through holes 190 are made at the spar 140 opposite ends, it must not be excluded that, in other embodiments, they may be made in other areas of the base frame 105, for instance in the slab-shaped body 115 or in specific attachments thereof.

In any case, it is preferred that the axes of each pair formed of a first through hole 195 and of a corresponding second through hole 190 are orthogonal to the support surface 110 and lie mutually spaced apart in a plane parallel to the spar 140 axis, i.e. parallel to the side edges 135 of the slab-shaped body 115.

The step 100 further comprises a footboard 205, which has and makes available a flat walkable footboard 210 on which a user can place his feet.

The footboard 205 is hinged to the base frame 105, in such a way as to rotate with respect to the latter around a preset hinging axis X which is parallel both to the walkable surface 210 of the footboard 205 and to the support surface 110 of the base frame 105.

The footboard 205 may have a substantially rectangular shape with a first pair of opposite edges 215 parallel to the hinging axis X and a second pair of opposite edges 220 orthogonal to the previous ones.

The distance between the edges 220 of the second pair may be substantially equal to the distance between the side edges 135 of the base frame 105, i.e. to the distance between spars 140.

In greater detail, the footboard 205 may comprise one or more slab-shaped elements 225 which make entirely available the walkable surface 210 and a perimeter framing or structure 230 which peripherally supports and surrounds said slab-shaped elements 225.

Each slab-shaped element 225 may be made of different materials, such as wood, stone, cement, metal or plastic, and may be possibly covered, at least at the walkable surface 210, with a coating layer, for example but not necessarily with artificial turf or non-slip material.

The perimeter framing 230 is preferably made of steel or another metal material and may be fixed to each slab-shaped element 225 with any known system, for instance by welding, snap-fitting or bolt-assembly.

In the example shown, hinging the footboard 205 and the base frame 105 may be obtained by means of a pair of articulated joints (only one is visible in the figures), each of which connects the perimeter framing 230 to a respective spar 140, for instance at the free terminal end of the second profile 170.

Each articulated joint may comprise a fork 240 rigidly fixed to the perimeter framing 230, which embraces the second profile 170 of the respective spar 140, and a pin 245, e.g. a bolt, having an axis coincident with the hinging axis X, which is fitted and tightened into corresponding coaxial holes obtained in the fork 240 and in the second profile 170 of the spar 140.

It must not be excluded, though, that in other embodiments, the articulated joints may be made in a different way.

The step 100 finally comprises locking means, which are able to lock the footboard 205 to the base frame 105 in a plurality of different angular positions around the hinging axis X.

These locking means may comprise two connecting elements 310, each of which is adapted to rigidly connect a primary coupling portion 315 belonging to the base frame 105 to a secondary coupling portion 320 belonging to the footboard 205, wherein said primary coupling 315 and secondary coupling portions 320 are both spaced apart from the hinging axis X.

The two connecting elements 310 may be mutually spaced apart in a direction parallel to the hinging axis X and may be mutually connected by a transverse support 312.

It is not excluded however that, in other embodiments, locking means may comprise only one of these connecting elements 310.

In the example shown, each connecting element 310 may be conformed as a rod or tip having an end that can be connected to the respective primary coupling portion 315 and the opposite end concurrently connectable to the respective secondary coupling portion 320.

For each connecting element 310, the primary coupling portion 315 may be defined in a corresponding spar 140, for instance in the first profile 155 of said spar 140 which is adapted to house the first connecting element 310.

In particular, the primary coupling portion 315 may be defined by a pair of holes 325 mutually coaxial and having axes parallel to the hinging axis X, which are respectively obtained in the two side walls of the first profile 155.

This pair of holes 325 is adapted to be aligned with the corresponding holes (not visible in the figures) made at the first end of the connecting element 310, such to receive an inserting pin 330, e.g. a bolt, enabling to stably fix the connecting element 310 to the base frame 105.

In particular, this pin 330 realises in itself an articulated joint which allows the connecting element 310 to rotate with respect to the base frame 105 around an articulation axis that is parallel and spaced apart from the hinging axis X.

The secondary coupling portion 320 of each connecting element 310 may instead be defined as a fork 335 which can be fixed to the footboard 205, for example the perimeter framing 230, and which is adapted to house the second end of the connecting element 310.

In particular, the secondary coupling portion 320 may be defined by a pair of mutually coaxial holes 340 and having axes that are parallel to the hinging axis X, which are respectively obtained in the two side walls of the fork 335.

This pair of holes 340 is adapted to align with corresponding holes (not visible in the figures) made at the second end of the connecting element 310, in such a way as to receive an inserting pin 345, e.g. a bolt, enabling to stably fix the connecting element 310 to the footboard 205.

In particular, also this pin 345 realises in itself an articulated joint enabling the connecting element 310 to rotate with respect to the footboard 205 around an articulation axis that is parallel and spaced apart from the hinging axis X.

However, when both ends of the connecting element 310 are concurrently connected respectively to the primary coupling portion 315 and to the secondary coupling portion 320, the connecting element 310 is rigidly locked both with respect to the base frame 105 and to the footboard 205, which are therefore prevented from rotating around the hinging axis X and forced to keep a preset mutual angular position.

It must in any case be specified that, in other embodiments, the articulated joints connecting the connecting element to the primary coupling portion 315 and to the secondary coupling portion 320 may be made in a completely different way.

In order to allow modifying the mutual angular position, the footboard 205 may comprise, for each connecting element 310, at least a second secondary coupling portion 320 that is distinct and preferably positioned at a radial distance with respect to the hinging axis X.

This second secondary coupling portion 320 may be substantially similar to the previous one, i.e. may be defined by a pair of mutually coaxial holes 340 and having axes parallel to the hinging axis X, which are respectively obtained in the two side walls of a fork 335 fixed to the footboard 205 and adapted to house the second end of the connecting element 310.

Thereby, by removing the pin 345, the connecting element 310 may be rotated around the pin 330 and the footboard 205 may be rotated around the hinging axis X, until reaching a configuration wherein the hole obtained at the second end of the connecting element 310 is aligned with the holes 340 of the second secondary coupling portion 320, afterwards the pin 345 may be inserted into these holes to lock the footboard 205 and the base frame 105 in the new angular position.

Similarly the base frame 105 may comprise, for each connecting element 310, one or more further primary coupling portions 315 that are distinct from one another and preferably positioned at different radial distances with respect to the hinging axis X.

Each of these additional primary coupling portions 315 may be similar to the previous one, i.e. may be defined by a pair of holes 325 mutually coaxial and having axes parallel to the hinging axis X, which are respectively obtained in the two side walls of the first profile 155 of the corresponding spar 140.

Thereby, by removing the pin 330, the connecting element 310 may be rotated around the pin 345 and the footboard 205 may be rotated round the hinging axis X, until reaching a configuration wherein the hole obtained at the first end of the connecting element 310 is aligned with the holes 325 of one of the further primary coupling portions 315, afterwards the pin 330 may be fitted into these holes, to lock the footboard 205 and the base frame 105 in the new angular position.

In order to further increase the number of obtainable angular positions, it is also possible to remove both the pin 330 and the pin 345 and hinge the element to a different primary coupling portion 315 and to a different secondary coupling portion 320.

It must however be highlighted that, to obtain a rigid connection between the base frame 105 and the footboard 205, it is not strictly required that the connecting element 310 is fixed to the primary coupling portion 315 and/or to the secondary coupling portion 320, as it is sufficient that the connecting element 310 is connected to said primary coupling 315 and secondary coupling portions 320 in such a way as to be locked thereto at least when such connection is simultaneous.

Therefore for example the connecting element 310 may be fixed to the primary coupling portion 315 and snap-fitted into the secondary coupling portion 320, as long as such snap-fitting (when realised) allows to lock in any case the connecting element 310 to the secondary coupling portion 320.

Similarly, the connecting element 310 may be fixed to the secondary coupling portion 320 and simply snap-fitted to the primary coupling portion 315, as long as such snap-fitting (when realised) allows to lock in any case the connecting element 310 to the primary coupling portion 315.

In some embodiments, the connecting element 310 may even be a component completely separated from the base frame 105 and the footboard 205 and be simply snap-fitted both to the primary coupling portion 315 and to the secondary coupling portion 320, as long as it is in any case locked to said primary 315 and secondary coupling portions 320 at least when both the aforesaid snap-fittings are realised simultaneously.

As shown in FIGS. 3 to 6 , in order to build a staircase 500 on a sloping ground T, it is possible to use a plurality of steps 100 having the previously set-forth features.

These steps 100 may be laid at different heights directly on the sloping ground T, making sure that the hinging axes X thereof are parallel and horizontal and, preferably, though not necessarily, that the walkable surfaces 210 thereof are aligned along the direction of maximum grade of the ground T.

In particular, the steps 100 may be arranged in such a way that the second through holes 190 of each step 100 are overlaid on the first through holes 195 of the adjacent step 100.

In the example shown, this effect may be obtained overlaying the flat attachments 180 of each step 100 to the flat attachments 160 of the adjacent step 100 (see details of FIGS. 4 and 6 ).

The steps 100 may thus be fixed to the ground simply using a plurality of anchoring pegs 285, each of which is adapted to be driven into the ground by passing it through a second through hole 190 of a step 100 and through the corresponding first though hole 195 of the adjacent step 100.

Thereby, each anchoring peg 285 is able to fix to the ground two steps 100 simultaneously and to mutually connect them, making sure that they keep a preset mutual distance and increasing the fastness of the staircase 500.

Once the steps 100 have been fixed, the footboards 205 may be rotated around the respective hinging axes X, until the walkable surfaces 210 are arranged substantially horizontally and directed upwards, and finally locked in position as previously outlined.

It must be noted that the above described assembly steps are not necessarily required to be carried out in the suggested order.

For example, if the ground grade T is known, the footboard 205 slope may be adjusted and locked before placing and fixing the steps 100 to the ground T.

Furthermore, it is possible to build the staircase 500 by placing and fixing on the ground one step 100 at a time.

In any case, thanks to this solution it is advantageously possible to build on the sloping ground T a staircase 500 formed of a plurality of steps 100 connected therebetween, by means of rather simple, quick operations and without having to carry out significant and expensive operations for preparing the ground T.

By varying the number of steps 100 used it is further advantageously possible to build a staircase 500 having any length according to the needs.

The steps 100 also have the advantage that they can be dismantled and assembled several times, for instance to move the staircase 500 on other grounds or to build other staircases 500.

Obviously, a person skilled in the art may bring several technical applicative changes to what hereinbefore described, without departing from the scope of the invention as claimed below. 

1. A step for building of a staircase, which comprises: a base frame provided with a flat support surface adapted to be laid and fixed on a ground, a footboard provided with a flat walkable surface, which is hinged to the base frame according to a hinging axis, parallel to the walkable surface and to the support surface of the base frame, and locking means adapted to lock the footboard, with respect to the base frame, in a plurality of different angular positions around said hinging axis.
 2. The step according to claim 1, wherein the locking means comprise at least one connecting element adapted to rigidly connect a primary coupling portion of the base frame to a secondary coupling portion of the footboard, said primary coupling portion and said secondary coupling portion both being spaced apart from the hinging axis.
 3. The step according to claim 2, wherein the base frame comprises a plurality of distinct primary coupling portions spaced apart from the hinging axis, and the connecting element is adapted to rigidly connect the secondary coupling portion with any one of said primary coupling portions.
 4. The step according to claim 3, wherein the connecting element is fixable to the secondary coupling portion through an articulated joint defining an articulation axis parallel and spaced apart with respect to the hinging axis.
 5. The step according to claim 3, wherein the footboard comprises a plurality of secondary coupling portions spaced apart from the hinging axis and the connecting element is adapted to rigidly connect the primary coupling portion with any one of said secondary coupling portions.
 6. The A step according to claim 5, wherein the connecting element is fixable to the primary coupling portion through an articulated joint defining an articulation axis parallel and spaced apart with respect to the hinging axis.
 7. The step according to claim 1, wherein the base frame comprises one or more first through holes, each of which is adapted to hold an anchoring peg adapted to be driven into the ground by passing through said first through hole.
 8. The step according to claim 7, wherein the base frame comprises one or more second through holes, each of which is adapted to be overlapped on a corresponding first through hole of another step to hold the same anchoring peg.
 9. A modular staircase comprising a plurality of steps according to claim 1, which are mutually connected and are arranged with their respective hinging axes parallel and spaced apart from each other.
 10. A method for building a staircase, comprising the steps of: prearrange a plurality of steps according to claim 1, placing these steps at different heights on a sloping ground, making sure that the support surfaces of these steps lay on the ground and that the hinging axes are horizontal, parallel and spaced apart from each other, fixing the base frame of each step to the ground, positioning the footboard of each step with respect to the corresponding base frame, by making it rotate around the respective hinging axis, in such a way as to arrange the respective walkable surface substantially horizontal, locking the footboard of each step to the corresponding base frame, in such a way as to prevent the mutual rotation around the respective hinging axis. 